1. Field of the Invention
The present invention relates to a multi-electrode catheter and in particular to a multi-electrode measurement catheter for measuring esophageal or diaphragmal electromyographic (EMG) signals.
2. Description of the Prior Art
It is known from, for example, U.S. Pat. Nos. 5,820,560 and 6,259,938 to provide a multi-electrode EMG measurement catheter that has a flexible, longitudinally extending, body for insertion into the esophagus of a patient and a number of externally mounted electrodes. The electrodes are located at longitudinally spaced-apart positions at a caudal section of the body in order to receive, in use, diaphragmal EMG signals. A corresponding number of electrical conductors in the form of insulated wires are provided and these are located within a lumen of the body. Each wire is connected to an associated different one of the external electrodes and runs within the same lumen from the associated electrode to a cephalad section of the body where an external connection to an EMG signal processing system may be established.